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0 pointsechoangle1y ago0 comments

> Having such a large difference in single-core performance, will negate the sizable difference in total core count (96 vs 16).

But why? Wouldn’t total score be approximately corecount*corescore? Of course it’s not exactly that because not all cores run full speed at the same time, but how are the cores weighted that 16 cores are better than 96 cores with half the speed each?

0 comments

wtallis1y ago

Geekbench 5 and earlier constructed the multi-core test as essentially running N independent copies of the single-core test. This effectively pretends that every subtest is embarrassingly parallel. Geekbench 6 switched to having the multi-core test actually operate like real multi-threaded software: a fixed-size problem is broken up to be divided among available cores, with a non-zero amount of coordination between threads and potential for less than perfectly linear scaling because Amdahl's Law isn't being ignored.

echoangleOP1y ago

But that’s a very specific thing to adjust a benchmark for, what if I want to host 50 VMs on one server for example? Then the 100 core server would be much better than the 16 core server, even though it has a lower benchmark value.

wtallis1y ago

It's not a "very specific" thing to adjust a benchmark for. It's the default case for practically all consumer workloads, and Geekbench is a consumer-focused benchmark.

tiffanyh1y ago

Because multicore cpu's don't scale linearly due to NUMA.

https://en.wikipedia.org/wiki/Non-uniform_memory_access

j / k navigate · click thread line to collapse

0 pointsechoangle1y ago0 comments

> Having such a large difference in single-core performance, will negate the sizable difference in total core count (96 vs 16).

0 comments

wtallis1y ago

echoangleOP1y ago

wtallis1y ago

It's not a "very specific" thing to adjust a benchmark for. It's the default case for practically all consumer workloads, and Geekbench is a consumer-focused benchmark.

tiffanyh1y ago

Because multicore cpu's don't scale linearly due to NUMA.

https://en.wikipedia.org/wiki/Non-uniform_memory_access

j / k navigate · click thread line to collapse